Fix #1251 -- Event list/calendar: Show "event almost sold out" state (#3063)

Co-authored-by: Richard Schreiber <schreiber@rami.io>

src/pretix/base/models/event.py

@@ -36,7 +36,7 @@ import logging
 import os
 import string
 import uuid
-from collections import OrderedDict
+from collections import Counter, OrderedDict, defaultdict
 from datetime import datetime, time, timedelta
 from operator import attrgetter
 from urllib.parse import urljoin
@@ -340,64 +340,104 @@ class EventMixin:
             )
         )
 
-    @cached_property
+    @property
     def best_availability_state(self):
+        return self.best_availability[0]
+
+    @property
+    def best_availability_is_low(self):
+        """
+        Returns ``True`` if the availability of tickets in this event is lower than the percentage
+        given in setting ``low_availability_percentage``.
+        """
+        if not self.settings.low_availability_percentage:
+            return False
+        ba = self.best_availability
+        if ba[1] is None or not ba[2]:
+            return False
+
+        percentage = ba[1] / ba[2] * 100
+        return percentage < self.settings.low_availability_percentage
+
+    @cached_property
+    def best_availability(self):
+        """
+        Returns a 3-tuple of
+
+        - The availability state of this event (one of the ``Quota.AVAILABILITY_*`` constants)
+        - The number of tickets currently available (or ``None``)
+        - The number of tickets "originally" available (or ``None``)
+
+        This can only be called on objects obtained through a queryset that has been passed through ``.annotated()``.
+        """
         from .items import Quota
 
         if not hasattr(self, 'active_quotas'):
             raise TypeError("Call this only if you fetched the subevents via Event/SubEvent.annotated()")
-        items_available = set()
-        vars_available = set()
-        items_reserved = set()
-        vars_reserved = set()
-        items_gone = set()
-        vars_gone = set()
-        items_disabled = set()
-        vars_disabled = set()
 
         if hasattr(self, 'disabled_items'):  # SubEventItem
             items_disabled = set(self.disabled_items.split(","))
+        else:
+            items_disabled = set()
 
         if hasattr(self, 'disabled_vars'):  # SubEventItemVariation
             vars_disabled = set(self.disabled_vars.split(","))
+        else:
+            vars_disabled = set()
 
+        # Compute the availability of all quotas and build a item→quotas mapping with all non-disabled items
         r = getattr(self, '_quota_cache', {})
+        quotas_for_item = defaultdict(list)
+        quotas_for_variation = defaultdict(list)
         for q in self.active_quotas:
-            res = r[q] if q in r else q.availability(allow_cache=True)
+            if q not in r:
+                r[q] = q.availability(allow_cache=True)
 
-            if res[0] == Quota.AVAILABILITY_OK:
+            if q.active_items:
-                if q.active_items:
+                for item_id in q.active_items.split(","):
-                    items_available.update(q.active_items.split(","))
+                    if item_id not in items_disabled:
-                if q.active_variations:
+                        quotas_for_item[item_id].append(q)
-                    vars_available.update(q.active_variations.split(","))
+            if q.active_variations:
-            elif res[0] == Quota.AVAILABILITY_RESERVED:
+                for var_id in q.active_variations.split(","):
-                if q.active_items:
+                    if var_id not in vars_disabled:
-                    items_reserved.update(q.active_items.split(","))
+                        quotas_for_variation[var_id].append(q)
-                if q.active_variations:
-                    vars_reserved.update(q.active_variations.split(","))
-            elif res[0] < Quota.AVAILABILITY_RESERVED:
-                if q.active_items:
-                    items_gone.update(q.active_items.split(","))
-                if q.active_variations:
-                    vars_gone.update(q.active_variations.split(","))
 
-        items_available -= items_disabled
+        if not self.active_quotas or (not quotas_for_item and not quotas_for_variation):
-        items_reserved -= items_disabled
+            # No item is enabled for this event, treat the event as "unknown"
-        items_gone -= items_disabled
+            return None, None, None
-        vars_available -= vars_disabled
-        vars_reserved -= vars_disabled
-        vars_gone -= vars_disabled
 
-        if not self.active_quotas or (
+        # We iterate over all items and variations and keep track of
-            not items_available and not items_reserved and not items_gone and not vars_gone and not vars_available and not vars_reserved
+        # - `best_state_found` - the best availability state we have seen so far. If one item is available, the event is available!
-        ):
+        # - `num_tickets_found` - the number of tickets currently available in total. We sum up all the items and variations, but keep
-            return None
+        #   track of them per-quota in `quota_used_for_found_tickets` to make sure we don't count the same tickets twice if two or more
+        #   items share the same quota
+        # - `num_tickets_possible` - basically the same thing, just with the total size of quotas instead of their currently availability
+        #   since we need that for the percentage calculation
+        best_state_found = Quota.AVAILABILITY_GONE
+        num_tickets_found = 0
+        num_tickets_possible = 0
+        quota_used_for_found_tickets = Counter()
+        quota_used_for_possible_tickets = Counter()
+        for quota_list in list(quotas_for_item.values()) + list(quotas_for_variation.values()):
+            worst_state_for_ticket = min(r[q][0] for q in quota_list)
+            quotas_that_are_not_unlimited = [q for q in quota_list if q.size is not None]
+            if not quotas_that_are_not_unlimited:
+                # We found an unlimited ticket, no more need to do anything else
+                return Quota.AVAILABILITY_OK, None, None
 
-        if items_available - items_reserved - items_gone or vars_available - vars_reserved - vars_gone:
+            if worst_state_for_ticket == Quota.AVAILABILITY_OK:
-            return Quota.AVAILABILITY_OK
+                availability_of_this = min(max(0, r[q][1] - quota_used_for_found_tickets[q]) for q in quotas_that_are_not_unlimited)
-        if items_reserved - items_gone or vars_reserved - vars_gone:
+                num_tickets_found += availability_of_this
-            return Quota.AVAILABILITY_RESERVED
+                for q in quota_list:
-        return Quota.AVAILABILITY_GONE
+                    quota_used_for_found_tickets[q] += availability_of_this
+
+            possible_of_this = min(max(0, q.size - quota_used_for_possible_tickets[q]) for q in quotas_that_are_not_unlimited)
+            num_tickets_possible += possible_of_this
+            for q in quota_list:
+                quota_used_for_possible_tickets[q] += possible_of_this
+
+            best_state_found = max(best_state_found, worst_state_for_ticket)
+        return best_state_found, num_tickets_found, num_tickets_possible
 
     def free_seats(self, ignore_voucher=None, sales_channel='web', include_blocked=False):
         qs_annotated = self._seats(ignore_voucher=ignore_voucher)
@@ -591,6 +631,7 @@ class Event(EventMixin, LoggedModel):
         self.settings.invoice_email_attachment = True
         self.settings.name_scheme = 'given_family'
         self.settings.payment_banktransfer_invoice_immediately = True
+        self.settings.low_availability_percentage = 10
 
     @property
     def social_image(self):

src/pretix/base/settings.py

@@ -1308,6 +1308,25 @@ DEFAULTS = {
                         "the email. Does not affect orders performed through other sales channels."),
         )
     },
+    'low_availability_percentage': {
+        'default': None,
+        'type': int,
+        'serializer_class': serializers.IntegerField,
+        'form_class': forms.IntegerField,
+        'serializer_kwargs': dict(
+            min_value=0,
+            max_value=100,
+        ),
+        'form_kwargs': dict(
+            label=_('Low availability threshold'),
+            help_text=_('If the availability of tickets falls below this percentage, the event (or a date, if it is an '
+                        'event series) will be highlighted to have low availability in the event list or calendar. If '
+                        'you keep this option empty, low availability will not be shown publicly.'),
+            min_value=0,
+            max_value=100,
+            required=False
+        )
+    },
     'event_list_availability': {
         'default': 'True',
         'type': bool,

src/pretix/control/forms/event.py

@@ -507,6 +507,7 @@ class EventSettingsForm(SettingsForm):
         'meta_noindex',
         'redirect_to_checkout_directly',
         'frontpage_subevent_ordering',
+        'low_availability_percentage',
         'event_list_type',
         'event_list_available_only',
         'frontpage_text',

src/pretix/control/templates/pretixcontrol/event/settings.html

@@ -314,6 +314,7 @@
                 {% if sform.event_list_available_only %}
                     {% bootstrap_field sform.event_list_available_only layout="control" %}
                 {% endif %}
+                {% bootstrap_field sform.low_availability_percentage layout="control" %}
 
                 {% url "control:organizer.edit" organizer=request.organizer.slug as org_url %}
                 {% propagated request.event org_url "meta_noindex" %}

src/pretix/presale/templates/pretixpresale/event/fragment_subevent_list.html

@@ -21,11 +21,15 @@
             <div class="col-md-2 text-right flip">
                 {% if subev.presale_is_running and event.settings.event_list_availability %}
                     {% if subev.best_availability_state == 100 %}
-                        <span class="label label-success">{% trans "Book now" %}</span>
+                        {% if subev.best_availability_is_low %}
+                            <span class="label label-success-warning">{% trans "Few tickets left" %}</span>
+                        {% else %}
+                            <span class="label label-success">{% trans "Book now" %}</span>
+                        {% endif %}
                     {% elif event.settings.waiting_list_enabled and subev.best_availability_state >= 0 %}
                         <span class="label label-warning">{% trans "Waiting list" %}</span>
                     {% elif subev.best_availability_state == 20 %}
-                        <span class="label label-warning">{% trans "Reserved" %}</span>
+                        <span class="label label-danger">{% trans "Reserved" %}</span>
                     {% elif subev.best_availability_state < 20 %}
                         {% if subev.has_paid_item %}
                             <span class="label label-danger">{% trans "Sold out" %}</span>

src/pretix/presale/templates/pretixpresale/fragment_calendar.html

@@ -27,7 +27,7 @@
                                     <li><a class="event {% if event.continued %}continued{% endif %} {% spaceless %}
     {% if event.event.presale_is_running and show_avail %}
         {% if event.event.best_availability_state == 100 %}
-            available
+            available {% if event.event.best_availability_is_low %} low {% endif %}
         {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
             waitinglist
         {% elif event.event.best_availability_state == 20 %}
@@ -68,7 +68,11 @@
                                             <span class="event-status">
                                                 {% if event.event.presale_is_running and show_avail %}
                                                     {% if event.event.best_availability_state == 100 %}
-                                                        <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                                        {% if event.event.best_availability_is_low %}
+                                                            <span class="fa fa-exclamation-circle" aria-hidden="true"></span> {% trans "Few tickets left" %}
+                                                        {% else %}
+                                                            <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                                        {% endif %}
                                                     {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
                                                         <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Waiting list" %}
                                                     {% elif event.event.best_availability_state == 20 %}

src/pretix/presale/templates/pretixpresale/fragment_day_calendar.html

@@ -40,7 +40,7 @@
                 <a class="event {% if event.continued %}continued{% endif %} {% spaceless %}
     {% if event.event.presale_is_running and show_avail %}
         {% if event.event.best_availability_state == 100 %}
-            available
+            available {% if event.event.best_availability_is_low %} low {% endif %}
         {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
             waitinglist
         {% elif event.event.best_availability_state == 20 %}
@@ -89,12 +89,16 @@
                         <span class="event-status">
                             {% if event.event.presale_is_running and show_avail %}
                                 {% if event.event.best_availability_state == 100 %}
-                                    <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                    {% if event.event.best_availability_is_low %}
-                                    {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
+                                        <span class="fa fa-exclamation-circle" aria-hidden="true"></span> {% trans "Few tickets left" %}
+                                    {% else %}
+                                        <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                    {% endif %}
+                                {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
                                     <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Waiting list" %}
-                                    {% elif event.event.best_availability_state == 20 %}
+                                {% elif event.event.best_availability_state == 20 %}
                                     <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Reserved" %}
-                                    {% elif event.event.best_availability_state < 20 %}
+                                {% elif event.event.best_availability_state < 20 %}
                                     {% if event.event.has_paid_item %}
                                         <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Sold out" %}
                                     {% else %}
@@ -104,9 +108,9 @@
                                 {% endif %}
                             {% elif event.event.presale_is_running %}
                                 <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
-                                {% elif event.event.presale_has_ended %}
+                            {% elif event.event.presale_has_ended %}
                                 <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Sale over" %}
-                                {% elif event.event.settings.presale_start_show_date and event.event.presale_start %}
+                            {% elif event.event.settings.presale_start_show_date and event.event.presale_start %}
                                 <span class="fa fa-ticket" aria-hidden="true"></span>
                                 {% blocktrans with start_date=event.event.presale_start|date:"SHORT_DATE_FORMAT" %}
                                     from {{ start_date }}

src/pretix/presale/templates/pretixpresale/fragment_week_calendar.html

@@ -12,7 +12,7 @@
                     <li><a class="event {% if event.continued %}continued{% endif %} {% spaceless %}
     {% if event.event.presale_is_running and show_avail %}
         {% if event.event.best_availability_state == 100 %}
-            available
+            available {% if event.event.best_availability_is_low %} low {% endif %}
         {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
             waitinglist
         {% elif event.event.best_availability_state == 20 %}
@@ -53,7 +53,11 @@
                             <span class="event-status">
                                 {% if event.event.presale_is_running and show_avail %}
                                     {% if event.event.best_availability_state == 100 %}
-                                        <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                        {% if event.event.best_availability_is_low %}
+                                            <span class="fa fa-exclamation-circle" aria-hidden="true"></span> {% trans "Few tickets left" %}
+                                        {% else %}
+                                            <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Book now" %}
+                                        {% endif %}
                                     {% elif event.event.settings.waiting_list_enabled and event.event.best_availability_state >= 0 %}
                                         <span class="fa fa-ticket" aria-hidden="true"></span> {% trans "Waiting list" %}
                                     {% elif event.event.best_availability_state == 20 %}

src/pretix/presale/templates/pretixpresale/organizers/index.html

@@ -81,11 +81,15 @@
                         <span class="label label-default">{% trans "Event series" %}</span>
                     {% elif e.presale_is_running and request.organizer.settings.event_list_availability %}
                         {% if e.best_availability_state == 100 %}
-                            <span class="label label-success">{% trans "Book now" %}</span>
+                            {% if e.best_availability_is_low %}
+                                <span class="label label-success-warning">{% trans "Few tickets left" %}</span>
+                            {% else %}
+                                <span class="label label-success">{% trans "Book now" %}</span>
+                            {% endif %}
                         {% elif e.settings.waiting_list_enabled and e.best_availability_state >= 0 %}
                             <span class="label label-warning">{% trans "Waiting list" %}</span>
                         {% elif e.best_availability_state == 20 %}
-                            <span class="label label-warning">{% trans "Reserved" %}</span>
+                            <span class="label label-danger">{% trans "Reserved" %}</span>
                         {% elif e.best_availability_state < 20 %}
                             {% if e.has_paid_item %}
                                 <span class="label label-danger">{% trans "Sold out" %}</span>

src/pretix/presale/views/widget.py

@@ -368,15 +368,20 @@ class WidgetAPIProductList(EventListMixin, View):
         availability = {}
         if ev.presale_is_running and event.settings.event_list_availability:
             if ev.best_availability_state == Quota.AVAILABILITY_OK:
-                availability['color'] = 'green'
+                if ev.best_availability_is_low:
-                availability['text'] = gettext('Book now')
+                    availability['color'] = 'green'
-                availability['reason'] = 'ok'
+                    availability['text'] = gettext('Few tickets left')
+                    availability['reason'] = 'low'
+                else:
+                    availability['color'] = 'green'
+                    availability['text'] = gettext('Book now')
+                    availability['reason'] = 'ok'
             elif event.settings.waiting_list_enabled and (ev.best_availability_state is not None and ev.best_availability_state >= 0):
                 availability['color'] = 'orange'
                 availability['text'] = gettext('Waiting list')
                 availability['reason'] = 'waitinglist'
             elif ev.best_availability_state == Quota.AVAILABILITY_RESERVED:
-                availability['color'] = 'orange'
+                availability['color'] = 'red'
                 availability['text'] = gettext('Reserved')
                 availability['reason'] = 'reserved'
             elif ev.best_availability_state is not None and ev.best_availability_state < Quota.AVAILABILITY_RESERVED:

src/pretix/static/pretixpresale/scss/_calendar.scss

@@ -58,15 +58,35 @@
       }
     }
 
-    &.available, {
+    &.available {
       background: lighten($brand-success, 48%);
       border-color: lighten($brand-success, 30%);
       border-left-color: $brand-success;
       color: darken($brand-success, 12%);
 
+      &.low {
+        border-left-color: lighten($brand-warning, 12%);
+      }
+
       &:hover {
         background: lighten($brand-success, 50%);
         border-color: $brand-success;
+
+        &.low {
+          border-left-color: $brand-warning;
+        }
+      }
+    }
+
+    &.waitinglist {
+      background: lighten($brand-warning, 41%);
+      border-color: lighten($brand-warning, 30%);
+      border-left-color: lighten($brand-warning, 12%);
+      color: #963;
+
+      &:hover {
+        background: lighten($brand-warning, 43%);
+        border-color: $brand-warning;
       }
     }
 
@@ -82,7 +102,6 @@
       }
     }
 
-
     &.available > *:first-child,
     &.continued > *:first-child,
     &.soon > *:first-child {

src/pretix/static/pretixpresale/scss/_theme.scss

@@ -121,3 +121,33 @@ footer {
     padding-bottom: 0;
   }
 }
+
+.label-success-warning {
+  @include label-variant($label-success-bg);
+
+  padding-left: 2.5em;
+  position: relative;
+  &::before {
+    font-family: FontAwesome;
+    text-rendering: auto;
+    -moz-osx-font-smoothing: grayscale;
+    -webkit-font-smoothing: antialiased;
+    color: white;
+    content: $fa-var-exclamation;
+    background: $label-warning-bg;
+
+    display: block;
+
+    position: absolute;
+    left: 0;
+    top: 0;
+    height: 100%;
+    width: 2em;
+
+    padding-top: .5em;
+    text-align: center;
+
+    border-top-left-radius: .25em;
+    border-bottom-left-radius: .25em;
+  }
+}

src/pretix/static/pretixpresale/scss/widget.scss

@@ -495,6 +495,12 @@
   .pretix-widget-event-availability-red.pretix-widget-event-calendar-event {
     background-color: $brand-danger;
   }
+  .pretix-widget-event-availability-low .pretix-widget-event-list-entry-availability span {
+    border-left: 10px solid $brand-warning;
+  }
+  .pretix-widget-event-availability-low.pretix-widget-event-calendar-event {
+    border-right: 10px solid $brand-warning;
+  }
 
   .pretix-widget-event-calendar {
     padding-top: 10px;

src/tests/base/test_models.py

@@ -2295,24 +2295,61 @@ class SubEventTest(TestCase):
 
     @classscope(attr='organizer')
     def test_best_availability(self):
-        q = Quota.objects.create(event=self.event, name='Quota', size=0,
-                                 subevent=self.se)
         item = Item.objects.create(event=self.event, name='Early-bird ticket', default_price=0, active=True)
+        o = Order.objects.create(
+            code='FOO', event=self.event, email='dummy@dummy.test',
+            status=Order.STATUS_PAID,
+            datetime=now(), expires=now() + timedelta(days=10),
+            total=Decimal("30"), locale='en'
+        )
+        OrderPosition.objects.create(
+            order=o,
+            item=item,
+            subevent=self.se,
+            variation=None,
+            price=Decimal("12"),
+        )
+        self.event.settings.low_availability_percentage = 60
+
+        # 1 quota - 1 item
+        q = Quota.objects.create(event=self.event, name='Quota', size=1,
+                                 subevent=self.se)
         q.items.add(item)
         obj = SubEvent.annotated(SubEvent.objects).first()
         assert len(obj.active_quotas) == 1
-        assert obj.best_availability_state == Quota.AVAILABILITY_GONE
+        assert obj.best_availability == (Quota.AVAILABILITY_GONE, 0, 1)
-        q2 = Quota.objects.create(event=self.event, name='Quota 2', size=1,
+
+        # 2 quotas - 1 item. Lowest quota wins.
+        q2 = Quota.objects.create(event=self.event, name='Quota 2', size=2,
                                   subevent=self.se)
         q2.items.add(item)
         obj = SubEvent.annotated(SubEvent.objects).first()
         assert len(obj.active_quotas) == 2
-        assert obj.best_availability_state == Quota.AVAILABILITY_GONE
+        assert obj.best_availability == (Quota.AVAILABILITY_GONE, 0, 1)
+
+        # 2 quotas - 2 items. Higher quota wins since second item is only connected to second quota.
         item2 = Item.objects.create(event=self.event, name='Regular ticket', default_price=10, active=True)
         q2.items.add(item2)
         obj = SubEvent.annotated(SubEvent.objects).first()
         assert len(obj.active_quotas) == 2
-        assert obj.best_availability_state == Quota.AVAILABILITY_OK
+        assert obj.best_availability == (Quota.AVAILABILITY_OK, 1, 2)
+        assert obj.best_availability_is_low
+
+        # 1 quota - 2 items. Quota is not counted twice!
+        q.size = 10
+        q.save()
+        q2.delete()
+        obj = SubEvent.annotated(SubEvent.objects).first()
+        assert len(obj.active_quotas) == 1
+        assert obj.best_availability == (Quota.AVAILABILITY_OK, 9, 10)
+        assert not obj.best_availability_is_low
+
+        # Unlimited quota
+        q.size = None
+        q.save()
+        obj = SubEvent.annotated(SubEvent.objects).first()
+        assert obj.best_availability == (Quota.AVAILABILITY_OK, None, None)
+        assert not obj.best_availability_is_low
 
 
 class CachedFileTestCase(TestCase):